Water or other fluids can collect in a propulsion system of an aircraft with a turbofan or a turbojet propulsion system. A propulsion system includes an aircraft engine, an inlet air duct, and an exhaust duct. Fluid that pools in the exhaust duct can cause numerous problems for an aircraft propulsion system, including corrosion, material incompatibility, mold and/or fungus growth, frozen water expansion and sensor malfunction. Some propulsion systems are more likely to pool fluids than others due to geometry.